Electric heating device for oil and gas wells



Oct. 28, 1941. T. A. RIAL ELECTRIC HEATING DEVICE FOR OIL AND GAS WELLS Filed Dec. 5, 1940 sur M aref ,uw 510 ZWIIIW Pk ,je

Z, rNvENToR al* ATTORNEYS Patented Oct. 28, 1941 UNITED STATES PATENT OFFICE ELECTRIC HEATING DEVICE FOR OIL AND GAS WELLS 2 Claims.

This invention relates to crude oil heaters, and more particularly to heating means adapted for use in the bottom of oil wells and the like.

When the flow of oil lags in a producing Well,

it is most often due to the congealing of paraffin and other congealing substances clogging the pores of the oil bea-ring formations in the immediate vicinity of the well and the most effective method of clearing up this condition is the application of controlled electrically produced heat to the oil or fluid in the Well. This heat penetrates into the oil bearing formation so as to melt the congealing substances, thereby causing the oil to run more freely and generally increases the productivity of the well. Also, the heated oil is more easily and economically extracted from the well. Accordingly, some means must be utilized by which controlled heat can be applied at and in the bottom of the Well adjacent the pump, and various heating devices have been developed to perform this function. However, so far as I am aware, no one has heretofore produced a compact and highly efficient heating unit having the particular advantageous features of those embodied in my invention.

A primary object of this invention is to provide heating means for scientifically heating the oil to obtain nearly complete recovery of oil from oil bearing formations, increase the productivity of oil from oil wells and obtain free and less costly extraction of the oil.

Another object of the invention is to provide an improved heating device whereby controlled heat may be efficiently applied to the oil and the oil bearing formations of a well.

A further object of the invention is the provision of a heating device which may be easily and safely inserted and withdrawn without damaging the well and which will eiiiciently operate at the bottom thereof independently of other well equipment.

Still another object of the invention is the provision of a simple, compact, durable and easily controlled device for accomplishing the above results.

These and other objects may be accomplished by employing my invention Which embodies among its features a metal casing threaded at the top and bottom and containing an electric heating element supported in insulating material which is electrically leakproof and is connected to lead wires which extend through the top of the casing, a top reducer element threaded on the casing, a closure element on the reducer, a sealing plug carrying said wires, in the closure, a supporting bail on the closure and a wire rope attached to the bail, and a bottom member threaded on the casing with an anchor post fixed thereto to support and stabilize the heater at the bottom of the well.

Other objects and features may become evident from the following disclosure when taken in connection with the accompanying drawing, in which:

Figure 1 is a cross sectional view of an oil well ywith my improved heater in operation,

Figure 2 is a vertical cross section of the heating unit, and

Figure 3 is a cross section taken on line 3-3 of Figure 2.

Referring to the drawing in detail, the casing I0 of my heating unit, as may be seen in Figure 2, is threaded at top and bottom and carries insulating material members I I and I2 Which in turn carry an electric heating element I3, held in holes in member II and resting on member I2. Lead Wires I4 are connected to binding posts on element I3 and extend upwardly therefrom.

Reducer element I5 is threaded onto the top of casing I0 and carries, through spacing means I6, the lead wires I4 which extend upwardly and are tightly fitted through a sealing plug I'I in closure member I8. The plug is of impervious material, such as rubber7 and makes a water-tight t with the wires to prevent the entry of the salt water or other material of the well from entering the unit and causing a short circuit. Closure element I8 also carries a bail I9, to which is attached the wire rope 20 to support the entire weight of the heating unit and lead Wires.

Threaded on the bottom of the casing I0 is an end member 2| which has, attached to its bottom, anchor post 22 to support the device on the bottom of the well.

It will be noted that, by the structure set out above, I produced a compact, durable and easily handled heating unit, which is readily adapted for the type of operation as shown in Figure 1. Here the well casing 23 contains a tubing and a pump 24 in the oil Well which is a cavity that has been created by shooting or other means. When the heating unit is lowered into the well cavity, as shown and a sufiicient amount of current is run through the lead wires I4, the oil in the well and oil bearing formation in the vicinity of the well will be heated and the oil caused to flow in increased quantity and thereby increase recovery through the Well.

Although a preferred embodiment is disclosed herein, I do not wish to be limited thereto but only by the scope of the appended claims.

Having thus described my invention, I claim:

l. In an oil Well heating unit, a longitudinally elongated casing having the bottom formed to provide a concave seat interiorly thereof, an insulating plate xed transversely in the upper portion of the casing, a lining member tted on the concave bottom seat and conforming thereto to provide an upper concave surface, an approximately U-shaped electric heating element mounted longitudinally in the casing and immovably supported therein, the said heating element having its bottom closed portion curved and fitted tightly on the concave surface of the lining member and having its upper spaced apart end portions extended through apertures in the top insulating plate, a closure fitting detachably connected with the upper end of the casing, and conductors extending through the said closure fitting and connected to the respective upper end portions of the heating element.

2. In a heating unit of the character described, an elongated tubular casing, a closure member threadedly connected with the bottom end of the casing and forming a concave seat interorly thereof, an anchor post attached to the said bottom end closure member and extending longitudinally therefrom, a reducer fitting threadedly connected with the upper end of the casing, an insulating liner mounted on the concave interior surface of the bottom closure member, an insulating plate mounted transversely in the upper portion of the casing and held between the top of the casing and the reducer fitting, a U-shaped electric heating element mounted longitudinally in the casing having its closed portion resting against the concave insulating liner at the bottom thereof and its upper spaced ends projecting through the insulating plate, a tubular closure member threadedly connected with the upper end of the reducer fitting having a reduced opening at the top thereof, a sealing plug fitted into the said reduced opening in the top closure member, lead wires extended through the said plug and connected to the electric heating element, and means for pivotally connecting a rope to the top closure member.

THOMAS A. RIAL. 

